collective.recipe.template 1.8

Genshi text templates

Starting with version 1.7 you can use genshi text templates.

A short example:

[buildout]
parts = message

[message]
recipe = collective.recipe.template[genshi]:genshi
input = templates/message.in
output = ${buildout:parts-directory}/etc/message
some-option = value

mymessage = Hello, World!

In the template you can use the exact same variables as you can use in the buildout configuration, but instead of colons as the separator you either have to use attribute access, or for options with a dash dictionary syntax. The global buildout config is accessible through parts, the current part through options.

For example an input file can look like this:

My top level directory is ${parts.buildout.directory}
Executables are stored in ${parts.buildout['bin-directory']}
Accessing the current part: ${options['some-option']}

Why another template recipe?

Both iw.recipe.template and inquant.recipe.textfile claim to do the same thing. I have found them to be undocumented and too buggy for real world use, and neither are in a public repository where I could fix them. In addition this implementation leverages the buildout variable substitution code, making it a lot simpler.

Simple creation of a file out of a template

Lets create a minimal buildout.cfg file:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = template
... offline = true
...
... [template]
... recipe = collective.recipe.template
... input = template.in
... output = template
... ''')

We create a template file:

>>> write('template.in',
... '''#
... My template knows about buildout path:
...   ${buildout:directory}
... ''')

Now we can run buildout:

>>> print system(join('bin', 'buildout')),
Installing template.

The template was indeed created:

>>> cat('template')
#
My template knows about buildout path:
.../sample-buildout

The variable buildout:directory was also substituted by a path.

Using inline input

For very short script it can make sense to put the source directly into buildout.cfg:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = template
... offline = true
...
... [template]
... recipe = collective.recipe.template
... input = inline:
...    #!/bin/bash
...    echo foo
... output = ${buildout:parts-directory}/template
... ''')

Now we can run buildout:

>>> print system(join('bin', 'buildout')),
Uninstalling template.
Installing template.

The template should have been created:

>>> cat('parts', 'template')
#!/bin/bash
echo foo

Normally the file mode gets copied from the template, but it can also be specified manually, which especially makes sense in this case:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = template
... offline = true
...
... [template]
... recipe = collective.recipe.template
... inline =
...    #!/bin/bash
...    echo foo
... output = ${buildout:parts-directory}/template
... mode = 755
... ''')

Run buildout again

>>> print system(join('bin', 'buildout')),
Uninstalling template.
Installing template.

The template should have the specified file mode:

>>> from os import stat
>>> from stat import S_IMODE
>>> print '%o' % S_IMODE(stat('parts/template').st_mode)
755

Creating a template in a variable path

Lets create a minimal buildout.cfg file. This time the output should happen in a variable path:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = template
... offline = true
...
... [template]
... recipe = collective.recipe.template
... input = template.in
... output = ${buildout:parts-directory}/template
... ''')

Now we can run buildout:

>>> print system(join('bin', 'buildout')),
Uninstalling template.
Installing template.

The template was indeed created:

>>> cat('parts', 'template')
#
My template knows about buildout path:
.../sample-buildout

Creating missing paths

If an output file should be created in a path that does not yet exist, then the missing items will be created for us:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = template
... offline = true
...
... [template]
... recipe = collective.recipe.template
... input = template.in
... output = ${buildout:parts-directory}/etc/template
... ''')

>>> print system(join('bin', 'buildout')),
Uninstalling template.
Installing template.

Also creation of several subdirectories is supported:

>>> write('buildout.cfg',
... '''
... [buildout]
... parts = template
... offline = true
...
... [template]
... recipe = collective.recipe.template
... input = template.in
... output = ${buildout:parts-directory}/foo/bar/template
... ''')

>>> print system(join('bin', 'buildout')),
Uninstalling template.
Installing template.

>>> cat('parts', 'foo', 'bar', 'template')
#
My template knows about buildout path:
.../sample-buildout

When changes happen to the output path, then the old path is removed on uninstall. Therefore the etc/ directory created above has vanished now:

>>> ls('parts')
d  foo

Substituting variables with options of other parts

When substituting variables in a template, dependencies on other buildout parts can occur. Buildout will resolve them by determining the values of those other parts’ options first. To see this, we create a buildout involving a template that uses a variable computed by a part that would not otherwise be built:

>>> write('dummy.py',
... '''
... class Recipe(object):
...
...     def __init__(self, buildout, name, options):
...         options['foo'] = 'bar'
...
...     def install(self):
...         return ()
...
...     def update(self):
...         pass
... ''')

>>> write('setup.py',
... '''
... from setuptools import setup
...
... setup(name='dummyrecipe',
...       entry_points = {'zc.buildout': ['default = dummy:Recipe']})
... ''')

>>> write('buildout.cfg',
... '''
... [buildout]
... develop = .
... parts = template
... offline = true
...
... [template]
... recipe = collective.recipe.template
... input = template.in
... output = template
...
... [other]
... recipe = dummyrecipe
... ''')

>>> write('template.in',
... '''#
... My template knows about another buildout part:
... ${other:foo}
... ''')

>>> print system(join('bin', 'buildout')),
Develop: '/sample-buildout/.'
Uninstalling template.
Installing other.
Installing template.

>>> cat('template')
#
My template knows about another buildout part:
bar

1.8 - 2010-06-08

• WARNING! Backward incompatible change for Genshi templates. It wasn’t possible to access parts with a dash in the name, so now you have to use ${parts.partname} or ${parts[‘part-name’]}. In addition it is now possible to access the current part with options. [fschulze]

• Import genshi modules very late to prevent issues with zc.buildout. [fschulze]

1.7 - 2010-05-21

• Added support for genshi text templates. Use them with this as the recipe: recipe = collective.recipe.template[genshi]:genshi Use a dot between the section name and the option name instead of a colon. [fschulze]

1.6 - 2010-02-24

• Output file mode is now assumed to be octal, like chmod. [elro]

• Inline template can now be specified with the inline option. [elro]

1.5 - 2010-02-23

• Add support for explicitly setting the output file mode. [witsch]

• Add support for inline templates. [witsch]

1.4 - 2009-07-29

• Fixed the way variables in templates are substituted to allow buildout to determine dependencies on other parts and prepare those correctly. [tlotze]

1.3 - 2009-04-28

• Add support for output path creation. You can do:

  output = /path/to/target

  and intermediate path items will be created if they do not exist. [ulif]

• Add tests. [ulif]

1.2 - 2008-12-09

(By accident the 1.1 release was marked as 1.2. So in fact they are the same.)

1.1 - 2008-12-09

• Correct handling of multiple variables in a line. Bugreport and patch from Roman Susi. [wichert]

1.0 - 2008-10-16

• Copy the mode of the input file to the output file. This makes it possible to create executable scripts. [wichert]

• Add missing link in README. [wichert]

1.0rc2 - 2008-07-04

• Add a MANIFEST.in with instructions to include docs/, otherwise the package will not install. [wichert]

1.0rc1 - 2008-07-04

• Initial release. [wichert]